Kowashiya

Sakaida Kou--full-time bartender, part-time detective. Or you call call him a spy of love. He's handsome and seductive, and he uses his charms to put young men in compromising positions so their lovers can have an excuse to dump them. But his latest target is a little different. Will Kou be able to seduce him and get him dumped without a backward glance?

Source: mangaupdates